Battery and system for in-situ electron paramagnetic resonance detection
By using a mesh aluminum mesh current collector and dry electrodes in the battery, combined with a specialized detection system, the problem of capturing intermediate states of battery reactions in existing technologies has been solved, and high-precision electron paramagnetic resonance detection has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGDAO UNIV
- Filing Date
- 2025-12-24
- Publication Date
- 2026-04-21
AI Technical Summary
Existing technologies struggle to accurately capture the true state of reaction intermediates and the changes in electronic valence states of transition metal ions in high-energy-density alkali metal secondary batteries, resulting in low accuracy in dynamic monitoring and testing.
An aluminum mesh is used as the positive electrode current collector, designed as a mesh structure to improve magnetic field penetration. The battery is composed of dry electrodes and materials without electron paramagnetic resonance signals. In-situ electron paramagnetic resonance detection is performed by combining an electrochemical testing system, an electromagnet system, a Hall probe, and a signal detection system.
It enables precise detection of changes in the valence state of transition metal ions and oxygen reaction intermediates during battery chemical reactions, thus improving testing accuracy.
Smart Images
Figure CN121906007A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of testing technology, and in particular to a battery and system for in-situ electron paramagnetic resonance detection. Background Technology
[0002] In high-energy-density alkali metal secondary batteries, the changes in the electronic valence state of transition metals and the evolution of oxygen-active species (such as singlet oxygen and free radicals) determine the actual electrochemical performance of the battery. The oxygen intermediates generated during the reaction process have extremely short lifetimes and high dynamism. It is necessary to develop comprehensive testing techniques to elucidate the reaction mechanism of the battery, guide the design of electrode materials for energy storage batteries, and realize the potential of high energy density.
[0003] However, in traditional spectroscopic techniques and electronic energy spectroscopy testing, it is difficult to accurately capture the true state of reaction intermediates and the changes in the electronic valence state of transition metal ions. Existing technologies are difficult to specifically analyze the evolutionary patterns of intermediate species, and the accuracy of dynamic monitoring and testing is low. Summary of the Invention
[0004] This application provides a battery and system for in-situ electron paramagnetic resonance detection, which helps to solve the problems of existing testing techniques, such as difficulty in accurately capturing the true state of reaction intermediates and changes in the electronic valence state of transition metal ions, difficulty in specifically analyzing the evolution law of oxygen reaction intermediate species, and low accuracy of dynamic monitoring and testing.
[0005] In a first aspect, embodiments of this application provide a battery for in-situ electron paramagnetic resonance detection, comprising: An encapsulation film, wherein the encapsulation film includes a positive electrode, a separator and a negative electrode stacked in sequence, and an electrolyte is disposed between the positive electrode and the negative electrode; A positive electrode lead, wherein the fixed end of the positive electrode lead is connected to the positive electrode plate, and the free end of the positive electrode lead extends out of the encapsulation film; The negative electrode lead has a fixed end connected to the negative electrode sheet and a free end extending out of the encapsulation film. The positive electrode includes a positive current collector and a positive electrode material, wherein the positive electrode material is attached to the positive current collector, and the positive current collector is an aluminum mesh.
[0006] In one possible implementation, the aluminum mesh includes a first end and a second end, the positive electrode material is attached to the first end of the aluminum mesh, the fixed end of the positive electrode lead is connected to the second end of the aluminum mesh, and the mesh size of the first end of the aluminum mesh is larger than that of the second end of the aluminum mesh.
[0007] In one possible implementation, the fixed end of the positive lead is woven into the second end of the aluminum mesh, so that the fixed end of the positive lead is connected to the positive electrode sheet.
[0008] In one possible implementation, the positive electrode is a dry electrode.
[0009] In one possible implementation, the encapsulation film is a material that is stretchable and free of electron paramagnetic resonance signals.
[0010] In one possible implementation, the encapsulation film is at least one material selected from polyethylene and polyester.
[0011] In one possible implementation, the positive electrode, the diaphragm, and the negative electrode are fixedly connected by a connecting wire made of a material that does not emit electron paramagnetic resonance signals.
[0012] One possible implementation also includes: A clamp is used to hold the outer side of the encapsulation film to increase the pressure between the positive electrode, the separator and the negative electrode. The clamp is made of a material that does not emit electron paramagnetic resonance signals.
[0013] In one possible implementation, the negative electrode sheet includes a negative current collector and an alkali metal material, the alkali metal material being attached to the negative current collector, the negative current collector being a copper sheet.
[0014] Secondly, embodiments of this application provide a system for in-situ electron paramagnetic resonance detection, comprising: An electrochemical testing system is used to electrically connect to the positive and negative leads of the battery under test, control the battery under test to perform reversible charging and discharging, and collect electrochemical signals, wherein the battery under test is the battery described in any one of the first aspects. An electromagnet system is used to provide a magnetic field for a resonant cavity, and the magnetic field generated by the electromagnet system is perpendicular to the electromagnetic waves conducted to the resonant cavity via a microwave bridge system. The probe system is used to provide electromagnetic frequency, electromagnetic wave frequency, and when the frequency and magnetic field strength of the electromagnetic wave meet the resonance absorption condition, the battery under test placed in the resonant cavity resonates and absorbs energy. A Hall probe is used to detect changes in the magnetic field within the resonant cavity and output a corresponding voltage signal. The signal detection system is used to determine the electronic valence state and oxygen intermediate of the battery under test based on the voltage signal output by the Hall probe.
[0015] The technical solution provided in this application can be used to detect electron spin changes in the battery chemical reaction process in situ, explore the intermediate structural characteristics of the surrounding environment in the energy storage battery, and improve the testing accuracy. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This application provides a battery for in-situ electron paramagnetic resonance detection in its embodiments; Figure 2 A schematic diagram of a system for in-situ electron paramagnetic resonance detection is also provided as an embodiment of this application; Figure 3 This is a schematic diagram of electron paramagnetic resonance test data of a battery provided in an embodiment of this application.
[0018] The symbols in the figure are: 101-sample rod, 102-positive electrode, 103-separator, 104-negative electrode, 105-encapsulation film, 106-positive lead, 107-negative lead, 201-sample rod, 202-electromagnetic system, 203-probe system, 204-Hall probe, 205-battery under test, 206-signal detection system. Detailed Implementation
[0019] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of this application.
[0020] To address the problems in existing technologies that make it difficult to accurately capture the true state of reaction intermediates, difficult to specifically analyze the evolution of oxygen reaction intermediate species and the changes in the electronic valence state of transition metal ions, and have low accuracy in dynamic monitoring and testing, this application provides a battery and system for in-situ electron paramagnetic resonance detection, which will be described in detail below with reference to the accompanying drawings.
[0021] See Figure 1 This is a battery provided in an embodiment of this application for in-situ electron paramagnetic resonance detection. For example... Figure 1As shown, the battery includes: an encapsulation film 105, within which a positive electrode 102, a separator 103, and a negative electrode 104 are sequentially stacked, with an electrolyte disposed between the positive electrode 102 and the negative electrode 104; a positive electrode lead 106, with its fixed end connected to the positive electrode 102 and its free end extending out of the encapsulation film 105; and a negative electrode lead 107, with its fixed end connected to the negative electrode 104 and its free end extending out of the encapsulation film 105. The positive electrode 102 includes a positive current collector and a positive electrode material, with the positive electrode material attached to the positive current collector, which is an aluminum mesh. In a specific implementation, the positive electrode lead 106 can be an aluminum wire, and the negative electrode lead 107 can be a copper wire.
[0022] In traditional batteries, the positive electrode current collector is typically made of aluminum sheet or aluminum foil. However, the applicant discovered through research that aluminum sheet or aluminum foil affects magnetic field penetration during in-situ electron paramagnetic resonance (EPR) detection. Based on this, embodiments of this application design the positive electrode current collector as a mesh structure (i.e., an aluminum mesh) to ensure better magnetic field penetration and improve detection performance.
[0023] In one possible implementation, the aluminum mesh includes a first end and a second end. Positive electrode material is attached to the first end of the aluminum mesh, and the fixed end of the positive electrode lead 106 is connected to the second end of the aluminum mesh. The mesh openings at the first end of the aluminum mesh are larger than those at the second end. Specifically, the positive electrode lead 106 can be an aluminum wire.
[0024] In practical applications, larger mesh sizes in the aluminum mesh result in better magnetic field penetration, but also worse contact between the positive electrode lead 106 and the aluminum mesh. To balance magnetic field penetration and the contact effect of the positive electrode lead 106, in this embodiment, the aluminum mesh is designed with non-uniform mesh sizes. Specifically, the mesh sizes are larger at the first end where the positive electrode material is attached, ensuring better magnetic field penetration (the test signal is mainly concentrated at the first end where the positive electrode material is attached); the mesh sizes are smaller at the second end where the positive electrode lead 106 is connected, ensuring better contact between the positive electrode lead 106 and the aluminum mesh.
[0025] In one possible implementation, the fixed end of the positive lead 106 is woven into the second end of the aluminum mesh, so that the fixed end of the positive lead 106 is connected to the positive electrode 102.
[0026] In traditional battery manufacturing processes, the positive electrode lead 106 is typically soldered to the positive electrode current collector using auxiliary materials such as tin. However, these auxiliary materials can generate electron paramagnetic resonance interference signals during testing, thus affecting the accuracy of the test. Therefore, in this embodiment, the fixed end of the positive electrode lead 106 is braided to the second end of an aluminum mesh. Since this solution eliminates the need for soldering auxiliary materials, it avoids generating interference signals, thereby improving test accuracy.
[0027] It should be noted that, in this embodiment of the application, since the fixed end of the positive lead 106 is woven on the second end of the aluminum mesh, in order to ensure the contact effect of the positive lead 106, the mesh of the second end of the aluminum mesh needs to be designed to be denser (smaller mesh).
[0028] In one possible implementation, the positive electrode 102 is a dry electrode. The specific preparation process of the dry electrode is as follows: the active material, conductive agent (the conductive agent used is Ketjenblack, which is a material without electron paramagnetic resonance signal) and binder are ground evenly in a mortar in a certain proportion to form a malleable block. Then, the block is repeatedly rolled by a roller press to form a malleable sheet. Finally, the pressed positive electrode material is rolled onto an aluminum mesh to prepare the positive electrode 102.
[0029] In this embodiment, since the positive current collector is an aluminum mesh, if a wet electrode is used, the electrode material is easily detached from the pores of the aluminum mesh. The dry electrode has stronger adhesion. Therefore, this embodiment adopts a dry electrode that is more compatible with the mesh structure of the aluminum mesh.
[0030] In one possible implementation, the encapsulation film 105 is a material that is stretchable and free of electron paramagnetic resonance signals.
[0031] In this embodiment, the encapsulation film 105 is made of a malleable material to ensure its adaptability to certain special battery systems (such as batteries that generate gas or require a specific gas atmosphere for reaction). Furthermore, the encapsulation film 105 is made of a material free of electron paramagnetic resonance signals, thus preventing the introduction of electron paramagnetic resonance interference signals.
[0032] In a specific implementation, the encapsulation film 105 is at least one material selected from polyethylene and polyester. Of course, other materials that meet the above requirements can also be used, and this application embodiment does not impose specific limitations on this.
[0033] In one possible implementation, the positive electrode 102, the diaphragm 103, and the negative electrode 104 are fixedly connected by a connecting wire made of a material that does not emit electron paramagnetic resonance signals.
[0034] In this embodiment, to ensure good contact between the positive electrode 102, the diaphragm 103, and the negative electrode 104, a connecting wire is used to fix them together. The connecting wire is made of a material that does not emit electron paramagnetic resonance signals, to avoid introducing electron paramagnetic resonance interference signals.
[0035] In one possible implementation, a clamp is also included, which is used to hold the outer side of the encapsulation film 105 to increase the pressure between the positive electrode 102, the separator 103 and the negative electrode 104, and the clamp is made of a material that does not have an electron paramagnetic resonance signal.
[0036] In this embodiment, the clamp further ensures good contact between the positive electrode 102, the diaphragm 103, and the negative electrode 104. The clamp is made of a material free of electron paramagnetic resonance signals to avoid introducing electron paramagnetic resonance interference signals.
[0037] In one possible implementation, the negative electrode 104 includes a negative current collector and an alkali metal material, the alkali metal material being attached to the negative current collector, which is a copper sheet.
[0038] In this embodiment, it is mainly used to detect the electron paramagnetic spin signal generated by the positive electrode. In actual operation, the interference signal generated by the negative electrode 104 can be easily distinguished and easily removed in the subsequent signal processing. Therefore, there is no need to make special designs for the negative electrode 104.
[0039] It should be added that, Figure 1 This is merely an illustrative example of an embodiment of this application and should not be construed as limiting the scope of protection of this application. For example, in Figure 1 For ease of illustration, the diaphragm 103 is drawn smaller than the positive electrode 102, and the negative electrode 104 is drawn smaller than the diaphragm 103. However, those skilled in the art should understand that in practical applications, the diaphragm 103 should be larger than both the positive electrode 102 and the negative electrode 104 to avoid short circuits between them. Additionally, Figure 1 The sample rod 101 in the figure does not belong to the battery, but is a fixed position of the example battery on the sample rod 101.
[0040] Corresponding to the above embodiments, this application also provides a system for in-situ electron paramagnetic resonance detection.
[0041] See Figure 2 The diagram below illustrates the structure of a system for in-situ electron paramagnetic resonance detection, as provided in this application embodiment. Figure 2 As shown, the system includes: an electrochemical testing system (not shown in the figure), a probe system 203, an electromagnet system 202, a Hall probe 204, and a signal detection system 206.
[0042] The electrochemical testing system is electrically connected to the positive electrode lead 106 and the negative electrode lead 107 of the battery under test 205, controls the battery under test 205 to perform reversible charging and discharging, and collects electrochemical signals. The battery under test 205 is the battery described in the above embodiments, and will not be described again in this application embodiment.
[0043] The electromagnet system 202 is used to provide a magnetic field for the resonant cavity. The magnetic field generated by the electromagnet system 202 is perpendicular to the electromagnetic wave conducted to the resonant cavity through the microwave bridge system.
[0044] The probe system 203 provides the electromagnetic wave frequency. When the frequency and magnetic field strength of the electromagnetic wave meet the resonance absorption condition, the battery under test 205, placed in the resonant cavity, resonates and absorbs energy. Specifically, the battery under test 205 can be fixed to the bottom of the sample rod 201 and then placed in the resonant cavity. The sample rod 201 can be made of a material that does not produce electron paramagnetic resonance signals, such as quartz.
[0045] The Hall probe 204 is used to detect changes in the magnetic field within the resonant cavity and accurately converts these changes into a voltage signal output, thereby enabling the measurement of the magnetic field strength.
[0046] The signal detection system 206 is used to detect the electronic valence state and oxygen intermediate of the battery under test 205 based on the voltage signal output by the Hall probe 204 during the charging and / or discharging process of the battery under test 205.
[0047] Specifically, the system for in-situ electron paramagnetic resonance detection provided in this application embodiment can be implemented based on electron paramagnetic resonance (EPR). The specific working principles of the electrochemical testing system, probe system 203, electromagnet system 202, Hall probe 204 and signal detection system 206 can be referred to EPR, and will not be repeated in this application embodiment.
[0048] To facilitate a better understanding of the technical solutions provided in the embodiments of this application by those skilled in the art, the testing process of the system for in-situ electron paramagnetic resonance detection is described below. It mainly includes the following steps.
[0049] Step 1: Fix the battery to be tested 205 to the bottom end of the sample rod 201, place the sample rod 201 into the resonant cavity, and place it under a constant magnetic field, for example, by wrapping and fixing the battery to the bottom end of the sample rod 201 through a flexible film (e.g., polyethylene or polyester film) that does not have an electron paramagnetic resonance signal. Step 2: Connect the positive electrode lead 106 and the negative electrode lead 107 of the battery 205 to be tested to the electrochemical testing device respectively; Step 3: Control the tested battery 205 to perform reversible charging and discharging within a certain voltage range using an electrochemical testing device, collect electrochemical signals, and ensure that electron paramagnetic resonance testing and electrochemical testing are started simultaneously, and collect electron paramagnetic resonance signals and electrochemical signals in real time.
[0050] See Figure 3 This is a schematic diagram of electron paramagnetic resonance test data for a battery provided in an embodiment of this application. Figure 3 As shown, the data indicates that a distinct peak belonging to singlet oxygen appeared after the battery discharged, demonstrating that the embodiments of this application can accurately capture the oxygen active intermediate state in the battery.
[0051] It should be noted that the battery provided in this application embodiment is applicable not only to ion batteries but also to other types of batteries, which will not be elaborated upon in this application embodiment. In specific implementation, the battery provided in this application embodiment can be any one of alkali metal ion batteries, alkali metal air batteries, alkali metal sulfur batteries, and alkali metal solid-state batteries.
[0052] The technical solution provided in this application can be used to detect changes in the valence state of transition metal ions and changes in oxygen reaction intermediates in the battery chemical reaction process in situ, thereby improving the testing accuracy.
[0053] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0054] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
[0055] The same or similar parts between the various embodiments in this specification can be referred to mutually. In particular, the terminal embodiments are basically similar to the method embodiments, so the description is relatively simple, and the relevant parts can be referred to the description in the method embodiments.
[0056] The embodiments described above do not constitute a limitation on the scope of protection of this application.
Claims
1. A battery for in-situ electron paramagnetic resonance detection, characterized in that, include: An encapsulation film, wherein the encapsulation film includes a positive electrode, a separator and a negative electrode stacked in sequence, and an electrolyte is disposed between the positive electrode and the negative electrode; A positive electrode lead, wherein the fixed end of the positive electrode lead is connected to the positive electrode plate, and the free end of the positive electrode lead extends out of the encapsulation film; The negative electrode lead has a fixed end connected to the negative electrode sheet and a free end extending out of the encapsulation film. The positive electrode includes a positive current collector and a positive electrode material, wherein the positive electrode material is attached to the positive current collector, and the positive current collector is an aluminum mesh.
2. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, The aluminum mesh includes a first end and a second end. The positive electrode material is attached to the first end of the aluminum mesh, and the fixed end of the positive electrode lead is connected to the second end of the aluminum mesh. The mesh size of the first end of the aluminum mesh is larger than that of the second end of the aluminum mesh.
3. The battery for in-situ electron paramagnetic resonance detection according to claim 2, characterized in that, The fixed end of the positive electrode lead is woven into the second end of the aluminum mesh, so that the fixed end of the positive electrode lead is connected to the positive electrode sheet.
4. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, The positive electrode is a dry electrode.
5. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, The encapsulation film is made of a material that is stretchable and does not contain electron paramagnetic resonance signals.
6. The battery for in-situ electron paramagnetic resonance detection according to claim 5, characterized in that, The encapsulation film is at least one material selected from polyethylene and polyester.
7. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, The positive electrode, the diaphragm, and the negative electrode are fixedly connected by a connecting wire made of a material that does not emit electron paramagnetic resonance signals.
8. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, Also includes: A clamp is used to hold the outer side of the encapsulation film to increase the pressure between the positive electrode, the separator and the negative electrode. The clamp is made of a material that does not emit electron paramagnetic resonance signals.
9. The battery for in-situ electron paramagnetic resonance detection according to claim 1, characterized in that, The negative electrode sheet includes a negative current collector and an alkali metal material, wherein the alkali metal material is attached to the negative current collector, and the negative current collector is a copper sheet.
10. A system for in-situ electron paramagnetic resonance detection, characterized in that, include: An electrochemical testing system is used to electrically connect to the positive and negative leads of the battery under test, control the battery under test to perform reversible charging and discharging, and collect electrochemical signals. The battery under test is the battery according to any one of claims 1-9. An electromagnet system is used to provide a magnetic field for a resonant cavity, and the magnetic field generated by the electromagnet system is perpendicular to the electromagnetic waves conducted to the resonant cavity via a microwave bridge system. The probe system is used to provide electromagnetic frequency, electromagnetic wave frequency, and when the frequency and magnetic field strength of the electromagnetic wave meet the resonance absorption condition, the battery under test placed in the resonant cavity resonates and absorbs energy. A Hall probe is used to detect changes in the magnetic field within the resonant cavity and output a corresponding voltage signal. The signal detection system is used to determine the electronic valence state and oxygen intermediate of the battery under test based on the voltage signal output by the Hall probe.